The need for playback ability and scoring arises in the use of ball serving machines and in the installation of practice alleys for games such as tennis, golf and baseball. In order to develop player ability, practice courts or alleys have been devised and marked off in the manner of the game involved; for example, tennis with a back court, a mid court, a fore court, and with a usual net. In order to conserve space, the half court has been developed for tennis practice alleys on a half court length, and the strategic areas of the absent and opposite half court being simulated in a damping screen that absorbs the impact of tennis balls driven thereagainst by a player working the first mentioned half court. As will be described, there is a usual net and the damping screen is hung vertically at a short distance behind the net; the damping screen being marked off in target areas which indicate various ball plays with respect to the absent opposite court half. It is necessary that the balls played over the net have their energy completely absorbed without bouncing back into the playing area, and to this end the free hanging screen is employed and from which the balls drop immediately behind the net and into a contained area for recycling through a ball machine characterized by a ball feeder and server motorized to recycle balls to the practice player on the half court, and all of which is installed within a berm disposed transversely of the court beneath the net.
In practice, the hanging screen is marked off into target areas to designate the impacts of tennis balls on trajectories toward the various strategic areas of the opposite, but absent, half court and namely the back court, the mid court, the fore court, and also to represent drive balls as well as lob balls. Velocity then has its affect upon the tennis balls impacting upon the aforesaid simulated areas of the damping screen, and it is an object of this invention to provide means to sense and/or categorize the velocity or impact forces of the balls upon the screen at each of the aforesaid designated areas. For example, a lob or drive ball traveling at excessive speed would be sensed as out of bounds; a ball traveling at moderate speed would be sensed as returnable; and a ball traveling at insufficient speed would be sensed as defeatable. It is to be understood that the target area designations, their proportions and values, and their relationship to velocity can be varied and applied as circumstances require, for instance to be adjusted to players having different abilities, experience and/or compensating for recognized classes of players.
An object of this invention is to provide sensor means cooperatively combined with a damping screen, to indicate impact with a restricted area thereof, without interferring with the energy absorbing efficiency of the screen. In practice, the screen is a sheet of pliable impact resistant material that will not rip or tear, such as for example a plastic sheet hung vertically. A feature of the present invention is that the sensor means is carried by the sheet, at the back side thereof, and preferably a separate sensor for each target area to be distinguished in scoring.
It is also an object of this invention to provide a sensor means that responds to indicate ball impacts of varying velocities, for example excessive, moderate or insufficient velocity. These comparative impacts are associated with designated areas where they have a recognized effect, as for example with the drive ball area and lob ball area.
It is still another object of this invention to provide scoring means as related to both area and velocity impact thereupon by tennis balls returned over the net to a damping screen, as above referred to; a scoring means that applies recognized values to the return plays as sensed by the impact upon the aforesaid designated areas. In carrying out this invention, the scoring means is electrical with a counter means to add and subtract from a player's score and commensurate with his ability to return tennis balls into impact engagement with strategic areas of the damping screen.